Revert "better handling of guestInstanceId"

This reverts commit ffd1a41.

js/components/frame.js

@@ -100,11 +100,19 @@ class Frame extends ImmutableComponent {
     // Create the webview dynamically because React doesn't whitelist all
     // of the attributes we need
     let webviewAdded = false
+    let guestInstanceId = null
     if (this.shouldCreateWebview()) {
+      // only set the guestInstanceId if this is a new frame
+      if (this.webview == null) {
+        guestInstanceId = this.props.frame.get('guestInstanceId')
+      }
       while (this.webviewContainer.firstChild) {
         this.webviewContainer.removeChild(this.webviewContainer.firstChild)
       }
       this.webview = document.createElement('webview')
+      if (guestInstanceId) {
+        this.webview.setAttribute('data-guest-instance-id', guestInstanceId)
+      }
       webviewAdded = true
     }
     this.webview.setAttribute('allowDisplayingInsecureContent', true)
@@ -131,16 +139,13 @@ class Frame extends ImmutableComponent {
       this.webview.allowRunningInsecureContent = true
     }
 
-    if (this.props.frame.get('guestInstanceId')) {
-      this.webview.setAttribute('data-guest-instance-id', this.props.frame.get('guestInstanceId'))
-    } else {
-      src = location
+    if (!guestInstanceId) {
       this.webview.setAttribute('src', isSourceAboutUrl(src) ? getTargetAboutUrl(src) : src)
     }
+
     if (webviewAdded) {
       let runOnDomReady = (e) => {
         this.webview.removeEventListener(e.type, runOnDomReady)
-        delete this.webview.dataset.guestInstanceId
         cb && cb()
       }
       this.webview.addEventListener('did-attach', runOnDomReady)

js/state/frameStateUtil.js

@@ -273,6 +273,7 @@ function undoCloseFrame (windowState, closedFrames) {
     closedFrames: closedFrames.pop(),
     frames: windowState.get('frames').splice(insertIndex, 0,
           closedFrame
+          .delete('guestInstanceId')
           .set('src', closedFrame.get('location'))),
     activeFrameKey: closedFrame.get('key')
   }

js/stores/windowStore.js

@@ -186,8 +186,7 @@ const doAction = (action) => {
 
       const key = action.key || windowState.get('activeFrameKey')
       windowState = windowState.mergeIn(frameStatePath(key), {
-        location: action.location,
-        guestInstanceId: undefined
+        location: action.location
       })
       if (!action.isNavigatedInPage) {
         windowState = windowState.mergeIn(frameStatePath(key), {